This invention relates to heavy industry conveyor belt pulleys, and more particularly to drum pulleys and the surface lagging for such pulleys. Drum pulleys have a smooth face surface and it is therefore necessary to provide a lagging cover for that surface. When the lagging becomes worn it must be replaced. Various forms of a lagging surface have been used heretofore, and, as far as known, they have all required too many parts and are impractical and expensive in their installation and capability of replacement. Further, it has not been possible heretofore to have just one size lagging surface which is adaptable for use with any different surface size drum pulley in that industry.
This invention provides a novel flexible structural lagging surface which is adaptable in one size for use with different sized drum pulleys.
This invention provides a one size flexible lagging structure adapted for use on different sized pulleys. The securement of the structure of the drum, being accomplished by only a few tack-weld spots, on the outer edges only, of each of the outermost metal sections, adapts this lagging structure for easy removal from the drum, by easy torch-burnable or carbon-arc-blowing release of each of the tack welded spots, and a removal of the lagging structure from the drum pulley.
Included in the basis for this application is the advantage of the flexible traction pad rubber connection of the parallel base-plates, with the traction pad extending on and over the plates, by the method of thus joining the plates in spaced relationship and allowing a small groove or gap to extend between the edges of the adjoining metal plate sections. As a result, the traction pad rubber is able to flex in the area between spaced-apart metal plate sections so that the lagging structure combination will conform to the surface of the drum to which it is attached. Thus, the one size structure, so formed as explained, is adaptable for use on different sized pulley drums.
Various types of pulley coverings and lagging structures are described in the following: U.S. Pat. Nos. 1,636,492 (Taylor); 2,707,403 (Thompson); 3,354,735 (Holz); 3,789,682 (Holz); 4,290,761 (Suginaka); 1,434,239 (Williams); and International Publication No. WO 82/00326 (Holz).
However, none of such prior devices are adapted to fit all different sized pulleys and do not exhibit the advantages provided by the lagging structure of this invention.